Atomic layer deposition methods

ABSTRACT

A first precursor gas is flowed to the substrate within the chamber effective to form a first monolayer on the substrate. A second precursor gas different in composition from the first precursor gas is flowed to the first monolayer within the chamber under surface microwave plasma conditions within the chamber effective to react with the first monolayer and form a second monolayer on the substrate which is different in composition from the first monolayer. The second monolayer includes components of the first monolayer and the second precursor. In one implementation, the first and second precursor flowings are successively repeated effective to form a mass of material on the substrate of the second monolayer composition. Additional and other implementations are contemplated.

TECHNICAL FIELD

[0001] This invention relates to atomic layer deposition methods.

BACKGROUND OF THE INVENTION

[0002] Semiconductor processing in the fabrication of integratedcircuitry typically includes the deposition of layers on semiconductorsubstrates. One such method is atomic layer deposition (ALD), whichinvolves the deposition of successive monolayers over a substrate withina deposition chamber typically maintained at subatmospheric pressure.With typical ALD, successive monoatomic layers are adsorbed to asubstrate and/or reacted with the outer layer on the substrate,typically by the successive feeding of different deposition precursorsto the substrate surface.

[0003] An exemplary ALD method includes feeding a single vaporizedprecursor to a deposition chamber effective to form a first monolayerover a substrate received therein. Thereafter, the flow of the firstdeposition precursor is ceased and an inert purge gas is flowed throughthe chamber effective to remove any remaining first precursor which isnot adhering to the substrate from the chamber. Subsequently, a secondvapor deposition precursor, different from the first, is flowed to thechamber effective to form a second monolayer on/with the firstmonolayer. The second monolayer might react with the first monolayer.Additional precursors can form successive monolayers, or the aboveprocess can be repeated until a desired thickness and composition layerhas been formed over the substrate.

SUMMARY

[0004] The invention comprises atomic layer deposition methods. In oneimplementation, a semiconductor substrate is positioned within an atomiclayer deposition chamber. A first precursor gas is flowed to thesubstrate within the chamber effective to form a first monolayer on thesubstrate. A second precursor gas different in composition from thefirst precursor gas is flowed to the first monolayer within the chamberunder surface microwave plasma conditions within the chamber effectiveto react with the first monolayer and form a second monolayer on thesubstrate which is different in composition from the first monolayer.The second monolayer includes components of the first monolayer and thesecond precursor. In one implementation, the first and second precursorflowings are successively repeated effective to form a mass of materialon the substrate of the second monolayer composition. In oneimplementation, after the second precursor gas flowing, a thirdprecursor gas different in composition from the first and secondprecursor gases is flowed to the second monolayer within the chambereffective to react with the second monolayer and form a third monolayeron the substrate which is different in composition from the first andsecond monolayers. In one implementation, after the second precursor gasflowing, the first precursor gas is flowed to the substrate within thechamber effective to react with the second monolayer and both a) removea component of the second monolayer to form a third compositionmonolayer on the substrate which is different in composition from thefirst and second monolayers; and b) form a fourth monolayer of the firstmonolayer composition on the third composition monolayer.

[0005] Other aspects and implementations not necessarily generic to anyof the above are contemplated and disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Preferred embodiments of the invention are described below withreference to the following accompanying drawings.

[0007]FIG. 1 is a diagrammatic sectional view of an exemplary atomiclayer deposition apparatus usable in accordance with an aspect of theinvention.

[0008]FIG. 2 is a series of diagrammatic molecular level views of anexemplary method in accordance with an aspect of the invention.

[0009]FIG. 3 is a series of diagrammatic molecular level views of anexemplary method in accordance with an aspect of the invention.

[0010]FIG. 4 is a series of diagrammatic molecular level views of anexemplary method in accordance with an aspect of the invention.

[0011]FIG. 5 is a series of common timelines showing exemplary gas flowsand power levels of processing in accordance with exemplary aspects ofthe invention.

[0012]FIG. 6 is an alternate series of common timelines to that depictedby FIG. 5.

[0013]FIG. 7 is another alternate series of common timelines to thatdepicted by FIG. 5.

[0014]FIG. 8 is still another alternate series of common timelines tothat depicted by FIG. 5.

[0015]FIG. 9 is yet another alternate series of common timelines to thatdepicted by FIG. 5.

[0016]FIG. 10 is another alternate series of common timelines to thatdepicted by FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] This disclosure of the invention is submitted in furtherance ofthe constitutional purposes of the U.S. Patent Laws “to promote theprogress of science and useful arts” (Article 1, Section 8).

[0018]FIG. 1 depicts an exemplary atomic layer deposition apparatususable in accordance with an aspect of the invention. Such an apparatusenables the generation of a surface microwave plasma within a chamberwithin which atomic layer deposition is conducted relative to asemiconductor substrate. In the context of this document, “surfacemicrowave plasma” is defined as a plasma generated in a gas against asubstrate being processed by transmitting microwave energy from aplurality of discrete, spaced microwave emitting sources, and whetherconducted in existing or yet-to-be-developed manners. One existingmanner of doing so is by use of an antenna, such as a surface planeantenna (SPA) or a radial line slot antenna (RLSA). By way of exampleonly, examples can be found in U.S. Pat. Nos. 6,399,520 and 6,343,565,which are hereby incorporated by reference herein.

[0019] Apparatus 10 is diagrammatically depicted as comprising adeposition chamber 12 having a semiconductor substrate 14 positionedtherein. In the context of this document, the term “semiconductorsubstrate” or “semiconductive substrate” is defined to mean anyconstruction comprising semiconductive material, including, but notlimited to, bulk semiconductive materials such as a semiconductive wafer(either alone or in assemblies comprising other materials thereon), andsemiconductive material layers (either alone or in assemblies comprisingother materials). The term “substrate” refers to any supportingstructure, including, but not limited to, the semiconductive substratesdescribed above. A suitable support or mechanism (not shown) can beprovided for supporting substrate 14 therein, and which might betemperature controlled, powered and/or otherwise configured forpositioning a substrate 14 within chamber 12 as desired.

[0020] A suitable microwave generator 16 is operatively connected with asurface plane antenna 18 received just above deposition chamber 12.Typically, surface plane antenna 18 is comprised of a metal materialhaving a plurality of microwave transmissive openings 20 formed thereinthrough which microwave energy generated by source 16 passes to withinchamber 12, and proximate the surface of substrate 14. The upper wall ofchamber 12 over which surface plane antenna 18 is received is also,therefore, provided to be microwave transmissive. Of course, some or allof surface plane antenna 18 could be provided within deposition chamber12. An exemplary preferred spacing from the upper surface of substrate13 to the lower surface of second antenna 28 is 65 mm. Of course,greater or small spacings can be utilized. In certain situations,spacings considerably less than 65 mm might be utilized. Further, inaddition to microwave, energy generation is also contemplated incombination with microwave energy generation, and whether within orexternally of chamber 12.

[0021] Exemplary precursor and/or purge gas inlets 22 and 24 are showndiagrammatically for emitting precursor and/or purge gases to withinchamber 12 intermediate substrate 14 and surface plane antenna 18. Avacuum draw-down line 26 is diagrammatically shown for exhaustingmaterial from chamber 26. The FIG. 1 apparatus is diagrammatic andexemplary in construction only, with any other suitable apparatus beingusable in accordance with the methodical aspects of the invention. Forexample, any alternate configuration, such as showerheads, multipleports or other means, whether existing or yet-to-be developed, are alsoof course contemplated for getting gas to the chamber and exhaustingmaterial from the chamber.

[0022] A semiconductor substrate, such as substrate 14, is positionedwithin an atomic layer deposition chamber. A first precursor gas isflowed to the substrate within the chamber, for example through one orboth of inlets 22 and 24, effective to form a first monolayer on thesubstrate. By way of example only, and with respect to forming anexemplary TiB₂ layer, an exemplary first precursor gas includes TiCl₄,and, for example, alone or in combination with inert or other gases. Anexemplary first monolayer produced from such TiCl₄ is TiCl_(x), forexample as depicted relative to FIG. 2. FIG. 2 illustrates exemplarysequential processing in an atomic layer deposition method utilizingTiCl₄. The far left illustrated portion of FIG. 2 depicts a suitablesubstrate surface 30 having a first monolayer 32 comprising TiCl_(x)adhered thereto. Such, by way of example only, is in the form oftitanium adhering to substrate surface 30 with chlorine atoms ormolecules extending outwardly from the titanium.

[0023] Typically, any remaining first precursor gas would then be purgedfrom the chamber using an inert purge gas, or by some other method.Regardless, a second precursor gas, different in composition from: thefirst precursor gas, is then flowed to the first monolayer within thechamber under surface microwave plasma conditions within the chambereffective to react with the first monolayer and form a second monolayeron the substrate which is different in composition from the firstmonolayer, with the second monolayer comprising components of the firstmonolayer and the second precursor. In the context of this document, agas being “different in composition” means some gas having an alternateand/or additional reactive component from the gas to which it is beingcompared.

[0024] The middle view in FIG. 2 depicts an exemplary preferred secondprecursor gas as comprising B₂H₆ and in an activated state under surfacemicrowave plasma conditions. As depicted in the far right view, such iseffective to react with first monolayer 32 to form a second monolayer 34which comprises TiB₂, with HCl as a by-product. Second monolayer 34comprises a component of the first monolayer (i.e., Ti) and a componentof the second precursor (i.e., B).

[0025] The above described first and second precursor flowings aresuccessively repeated effective to form a mass of material on thesubstrate of the second monolayer composition. The fabricated mass mightcomprise, consist essentially of, or consist of the second monolayercomposition. For example, the invention contemplates the possibility offabricating the mass to include materials other than solely the secondmonolayer composition, for example by introducing alternate first and/orsecond precursor gases as compared to only using the above-describedfirst and second precursor gases in forming the mass of material on thesubstrate.

[0026] The exemplary above-described process has the second monolayercomponent from the first monolayer as being a metal in elemental form(i.e., titanium), wherein the second monolayer comprises a conductivemetal compound. Further in one preferred embodiment, the mass ofmaterial is formed to be conductive. By way of example only, analternate of such processing would be to utilize a first precursor gascomprising TaCl₅ to form a first monolayer comprising TaCl_(x) In suchinstance, an exemplary second precursor gas comprises NH₃ to form asecond monolayer comprising TaN. As with the first-described embodiment,inert gases, flow rates, power, temperature, pressure and any otheroperating parameter can be selected and optimized by the artisan, withno particular one or set of parameters being preferred in the context ofthe invention.

[0027] Alternately by way of example only, the second monolayer could beformed to comprise a dielectric material, and further by way of exampleonly, the mass of material fabricated to be insulative. For example forforming an insulative mass comprising Al₂O₃, exemplary gases includetrimethylaluminum as a first precursor gas, and O₃ and/or H₂O as asecond precursor gas.

[0028] Also in any of the above-described and subsequent embodiments,the first precursor gas flowing can be with or without plasma within thechamber, for example with our without surface microwave plasmageneration within the chamber with the first precursor gas flowing.Further, remote plasma generation could also be utilized with the firstprecursor gas flowing; and also with the second precursor gas flowing incombination with surface microwave plasma conditions within the chamberduring the second precursor gas flowing.

[0029] In one implementation, an atomic layer deposition method includesthe above generically described first and second precursor gas flowings.After the second precursor gas flowing, a third precursor gas differentin composition from the first and second precursor gases is flowed tothe second monolayer within the chamber effective to react with thesecond monolayer and form a third monolayer on the substrate which isdifferent in composition from the first and second monolayer. The first,second and third precursor flowings can be successively repeatedeffective to form a mass of material on the substrate which comprises,consists essentially of or consists of the third monolayer composition.By way of example only in accordance with this implementation, exemplaryprocessing is further described with reference to FIG. 3 in theformation of a third monolayer comprising an aluminum oxide.

[0030] Specifically, the far left illustrated view of FIG. 3 depicts theresult of flowing a first precursor gas comprising trimethylaluminum toform a first monolayer 40 comprising AlCH_(x) onto a substrate surface30. A second precursor gas, for example H₂, is flowed to the firstmonolayer within the chamber under surface microwave plasma conditionswithin the chamber effective to react with first monolayer 40 and form adifferent composition second monolayer 42 on the substrate. Illustratedsecond monolayer 42 comprises a component from first monolayer 40 (Al)and a component from the second precursor (H). A third precursor gas(i.e., O₃ and/or H₂O) is flowed to second monolayer 42 within thechamber effective to react therewith and form a third monolayer 44(i.e., AlO_(x)) on substrate 30 which is different in composition fromfirst monolayer 40 and second monolayer 42. Of course, such processingcan be repeated to deposit a desired thickness aluminum oxide comprisinglayer by atomic layer deposition. Further of course, one, both orneither of the first and third precursor gas flowings could compriseremote and/or chamber generated plasma, and for example include surfacemicrowave plasma conditions.

[0031] By way of example only and where a desired finished product isTiN, an exemplary alternate first precursor gas is TiCl₄ to form amonolayer comprising TiCl_(x). An exemplary second precursor gas couldstill comprise H₂, with an exemplary third precursor gas comprising NH₃.Further by way of example, another deposited material is TaN as thethird monolayer. An exemplary first precursor gas is TaCl₅ to form thefirst monolayer to comprise TaCl_(x). An exemplary second precursor gasis H₂ and an exemplary third precursor gas is NH₃.

[0032] In one implementation, processing occurs as described abovegenerically with respect to the first and second precursor gas flowings.After the second precursor gas flowing, the first precursor gas isflowed to the substrate within the chamber effective to react with thesecond monolayer and both a) remove a component of the second monolayerto form a third composition monolayer on the substrate which isdifferent in composition from the first and second monolayers, and b)form a fourth monolayer of the first monolayer composition on the thirdcomposition monolayer. By way of example only, exemplary processing ismore specifically described in FIG. 4 in connection with the fabricationof an elemental tantalum layer.

[0033] The far left illustrated view of FIG. 4 depicts processing afterflowing a first precursor gas comprising TaCl₅ to form a first monolayer60 comprising TaCl_(x) onto a substrate surface 30. This is followed byflowing a second precursor gas (i.e., H₂) which is different incomposition from the first precursor gas to the first monolayer withinthe chamber under surface microwave plasma conditions within the chambereffective to react with the first monolayer to form a second monolayer62 on the substrate which is different in composition from the firstmonolayer. Second monolayer 62 comprises a component of the firstmonolayer (i.e., Ta) and a, component of the second precursor (i.e., H).Subsequently, the first precursor gas (i.e., TaCl₅) is flowed to thesubstrate within the chamber effective to react with second monolayer 62to both a) remove a component of the second monolayer (i.e., H) to forma third composition monolayer 64. (i.e., Ta), which is different incomposition from first monolayer 60 and second monolayer 62, and b) forma fourth monolayer 66 (i.e., TaCl_(x)) of the first monolayercomposition on third composition monolayer 64. Such can be successivelyrepeated to form a mass of material on the substrate comprising,consisting essentially of, or consisting of the third compositionmonolayer. Again, the first and third precursor flowings can be with orwithout plasma within the chamber, for example with or without surfacemicrowave plasma.

[0034] The depicted and preferred FIG. 4 processing forms the thirdcomposition monolayer to comprise a metal in elemental form. By way ofexample only, alternate exemplary processing for the fabrication of atitanium layer might utilize a first precursor gas comprising TiCl₄ toform the first monolayer to comprise TiCl_(x). In such instance, apreferred exemplary second precursor again comprises H₂.

[0035] The invention has particular advantageous utility where the firstmonolayer is of a composition which is substantially unreactive with thesecond precursor under otherwise identical processing conditions but forpresence of surface microwave plasma within the chamber. Firstmonolayers as described above with reference to FIGS. 2-4 can constitutesuch compositions.

[0036] At least with respect to a second precursor gas flowing which isdifferent from the first to form the first monolayer within the chamberunder surface microwave plasma conditions, the various above-describedprocessings can provide better uniformity and utilize lower ion energyin facilitating an atomic layer deposition which is plasma enhanced incomparison to higher ion energy plasmas which are not expected toprovide as desirable a uniformity.

[0037] The above-described processings can occur in any manner asliterally stated, for example with or without intervening inert purgegas flowings and under any existing or yet-to-be developed processingparameters. Further by way of example only, the openings within theantenna might be made to be gas transmissive as well as microwavetransmissive and the antenna provided with the chamber. In suchinstance, gas might be flowed through the plurality of openings whiletransmitting microwave energy through the plurality of openings to theprocessing chamber effective to form a surface microwave plasma onto asubstrate received within the processing chamber. Gas inlets could beconfigured to flow first to the antennas, and then into the chamberthrough the openings with the microwave energy which is transmittedthrough the same openings, or through different openings. Suchprocessing can be void of flowing any gas to the chamber duringtransmitting of the microwave energy other than through the plurality ofopenings, if desired.

[0038] Further by way of example only, exemplary preferred processingfor carrying out the above exemplary methods is described below inconjunction with TiCl₄ as a first precursor gas and H₂ as a secondprecursor gas, and utilizing an inert purge gas comprising helium. Thebelow-described preferred embodiments/best modes disclosure forpracticing exemplary methods as described above are also considered toconstitute independent inventions to those described above, and as aremore specifically and separately claimed.

[0039] Referring generally to FIGS. 5-9, such essentially depict acommon horizontal timeline showing different respective gas pulsesseparately broken out in the form of a first precursor gas (i.e.,TiCl₄), an inert purge gas (i.e., He), and a second precursor gas (i.e.,H₂). The H₂ timeline also has associated therewith dashed lines intendedto depict the application of energy at least the elevated-most surfacesof which are intended to depict a power level effective to form a plasmaof the exemplary H₂ gas flowing within the chamber. Such might, andpreferably does, constitute surface microwave plasma generation within asuitable chamber, for example as described above in connection with thefirst above embodiments, although is not so limited with respect to theFIGS. 5-9 embodiments unless found literally in a claim under analysis.

[0040] Referring initially to FIG. 5, a semiconductor substrate would bepositioned within an atomic layer deposition chamber. A first precursorgas is flowed to the substrate within the chamber effective to form afirst monolayer on the substrate, for example as depicted by a TiCl₄ gaspulse P1. Plasma generation might or might not be utilized. Afterflowing the first monolayer, an inert purge gas is flowed to thechamber, for example as depicted by a helium gas pulse P2. After flowingthe inert purge gas, a second precursor gas is flowed to the substrateunder plasma conditions within the chamber effective to form a secondmonolayer on the substrate which is different in composition from thefirst monolayer; for example as depicted by an H₂ gas pulse P3. Thesecond precursor gas is different in composition from the firstprecursor gas.

[0041] The plasma conditions within the chamber comprise the applicationof energy to the chamber at some power level 40 capable of sustainingplasma conditions within the chamber with the second precursor gas P3.The application of such energy to the chamber commences along anincreasing power level 42 up to plasma capable power level 40 at a timepoint 44 prior to flowing the second precursor gas to the chamber, forexample as depicted at time point 45. In the exemplary depicted FIG. 5embodiment, the power level increasing along line 42 is continuous, andalso preferably at a substantially constant rate. The first monolayermight be formed in the presence or absence of plasma within the chamber.Further in one preferred embodiment in connection with FIGS. 5-9, andfor example as described in the initial embodiments, the secondmonolayer formed may result from a reaction with the first monolayer,with the second monolayer comprising components of the first monolayerand the second precursor. Further in the exemplary FIG. 5 depictedembodiment, inert purge gas flowing P2 and second precursor gas flowingP3 do not overlap. By way of example only, exemplary time periods forall pulses is one second. Although of course, greater, less and/orunequal times could be utilized. After forming the second monolayer,another inert purge gas flowing P4 (the same or different in compositionin some way to that of the first precursor gas) is begun prior tocommencing a reducing of the plasma capable power. For example, FIG. 5depicts the P4 pulse commencing at a time point 46 which is before atime point 48 when a reducing from the plasma capable power starts tooccur.

[0042] In the depicted FIG. 5 embodiment, and by way of example only,second precursor pulse P3 and the other inert purge gas pulse P4 do notoverlap. Further, the second precursor gas flowing to the chamber isceased prior to commencing a reducing of the plasma capable power. Byway of example, such is depicted at a time point 50, where the secondprecursor gas flow is ceased, in comparison with later-in-time point 48where power begins to reduce from power level 40. The above exemplaryprocessing can be repeated, of course, for example as shown by gaspulses P5, P6 and P7.

[0043] Another exemplary embodiment is described with reference to FIG.6. As with the FIG. 5 embodiment, a semiconductor substrate ispositioned within an atomic layer deposition chamber and a firstprecursor gas is flowed to the substrate within the chamber effective toform a first monolayer on the substrate. Such is depicted by theexemplary P1 TiCl₄ pulsing. After forming the first monolayer, a secondprecursor gas is flowed to the substrate under plasma conditions withinthe chamber effective to form a second monolayer on the substrate whichis different in composition from the first monolayer. The secondprecursor gas is different in composition from the first precursor gas,and is depicted by P3 as an example only with respect to an exemplary H₂second precursor gas flowing.

[0044] In FIG. 6, plasma generation of the second precursor gas withinthe chamber occurs from a second applied power level of energy 40 to thechamber which is capable of generating plasma within the chamber. Somesteady-state, first-applied power level of such energy is applied to thechamber at some point prior at least prior to applying thesecond-applied power level of such energy 40. An exemplary steady-state,first-applied power level 62 is depicted in FIG. 6 which is less thansecond-applied power level 40, with an increasing from first-appliedpower 62 to second-applied power level 40 occurring along a line 64.

[0045] In one preferred embodiment, steady-state first power 62 isinsufficient to generate plasma from the flowing second precursor gas.In one preferred embodiment, steady-state first power 62 is insufficientto generate plasma from the flowing first precursor gas. In the depictedexemplary preferred FIG. 6 embodiment, steady-state first power 62 isapplied during first precursor flowing P1, and under conditionseffective to form a first monolayer on the substrate under non-plasmaconditions within the chamber. In one embodiment, first power level 62can be considered as a base power level of energy.

[0046]FIG. 6 also depicts a purge gas flowing P2 to the chamberintermediate first precursor gas flowing P1 and second precursor gasflowing P2, with steady-state first power 62 being applied during purgegas flowing P2. Further, base power level 62 is raised to power level 40during a portion of inert purge gas flowing P2.

[0047] In the preferred FIG. 6 embodiment, a purge gas flowing P4 occursafter the second precursor gas flowing P3, with a return to—power level62 occurring during such purge gas flowing P4 and after a ceasing offlow of second precursor gas P3. The exemplary processing is depicted asbeing repeated in connection with gas pulses P5, P6 and P7, and providesbut one example of depositing one or more additional monolayers onto thesecond monolayer. FIG. 6 depicts commencing the raising or increasing ofthe power level at a point in time 66 which is prior to a point in time68 when second precursor gas flowing P3 begins. Further in the preferredFIG. 6 embodiment, reducing from power level 40 is commenced at a timepoint 70 which occurs after a time point 72 where second precursor gaspulse P3 flow is ceased.

[0048] By way of example only, FIGS. 5 and 6 illustrate exemplarypreferred embodiments wherein the respective gas pulses in no wayoverlap. The invention also contemplates at least some overlapping ofthe gas pulses, of course. By way of example only, and particularly withreference to the second precursor gas pulsing, exemplary overlappingsare described with reference to FIGS. 7-10.

[0049] Referring initially to FIG. 7, such is the same as FIG. 6 exceptthe inert P2 pulse is extended to continue over the P3 pulse, with theinert P2 pulse flowing ceasing after a ceasing of second precursor gasflowing P3.

[0050] Referring to FIG. 8, a first precursor gas is flowed to thesubstrate within an atomic layer deposition chamber effective to form afirst monolayer on the substrate, for example as depicted with respectto TiCl₄ with a gas pulse P1. After forming the first monolayer, aninert purge gas is flowed to the chamber, for example as designated byhelium gas pulse P2. After flowing the inert purge gas, a secondprecursor gas is flowed to the substrate under plasma conditions withinthe chamber effective to form a second monolayer on the substrate whichis different in composition from the first monolayer. In some manner,the second precursor gas is different in composition from the firstprecursor gas, for example as depicted in FIG. 8 by H₂ pulse P3.

[0051] As also depicted in FIG. 8, the second precursor gas flowingunder plasma conditions within the chamber commences at an exemplarytime point 76 before a time point 77 when inert purge gas flow P2 isceased. Further, inert purge gas flow P2 ceases at the exemplary timepoint 77 after the commencing and while the second precursor gas flowingunder plasma conditions within the chamber is occurring. Further, FIG. 8depicts that the plasma conditions within the chamber comprise theapplication of energy to the chamber at a power level 40 which iscapable of sustaining plasma conditions within the chamber with thesecond precursor gas. FIG. 8 also depicts a minimum application of abase power level 62, and a raising therefrom to power level 40 along asegment 78. However also with respect to the FIG. 8 exemplaryembodiment, an aspect of the invention contemplates zero power beingapplied as: opposed to some base level 62. Regardless and in anon-limiting fashion, FIG. 8 also depicts second precursor gas pulse P3commencing at a time point 80 and the power level increasing along line78 commencing at a time point 82 which is after time point 80.

[0052] After forming the second monolayer, another inert purge gas flowP4 is depicted as commencing at a point in time 84 which is prior to apoint in time 86 when the second precursor gas flow is ceased. Ofcourse, such processing can be repeated for example as depicted by gaspulses P5, P6 and P7.

[0053] By way of example only, FIG. 9 depicts an alternate embodimentwhereby the commencing of an application of energy to the chamber at theincreasing power level up to a plasma capable power level 40 occurscommensurate with point in time 80 constituting the beginning of theflow of the second precursor gas to the chamber. Also by way of exampleonly, FIG. 8 depicts power levels starting from and returning to zero,with the arrival at zero power also occurring at time point 86 when theflow of the second precursor is ceased.

[0054] Further by way of example only, FIG. 10 depicts a process wherebythe application of energy to the chamber at the increasing power levelup to power level 40 commences at a time point 90 which is prior totimer-point 80 when the flow of the second precursor gas to the chambercommences.

[0055] By way of example only, plasmas generated from microwaves aretypically characterized by a very shallow skin depth, with the powerbeing very effectively consumed in a very small volume. Surfacemicrowave plasma typically results from generation of uniform plasmafrom microwave by means of distributing or spreading out the microwaveenergy prior to entry into the reaction chamber. The microwave power istypically converted from a waveguide transmission mode into waves thatrun parallel to an upper reactor plane antenna/window. This conversionto surface wave is produced by a diverting antenna that acts to reflectthe microwaves. Once the microwaves are running parallel to the upperplane antenna, small openings in the plane antenna allow portions of themicrowave to be released to the reaction chamber thus spreading thepower over the desired area. The periodicity of the openings in theplane antenna determine the locality and uniformity of the power spread.

[0056] In compliance with the statute, the invention has been describedin language more or less specific as to structural and methodicalfeatures. It is to be understood, however, that the invention is notlimited to the specific features shown and described, since the meansherein disclosed comprise preferred forms of putting the invention intoeffect. The invention is, therefore, claimed in any of its forms ormodifications within the proper scope of the appended claimsappropriately interpreted in accordance with the doctrine ofequivalents.

1. An atomic layer deposition method comprising: positioning asemiconductor substrate within an atomic layer deposition chamber;flowing a first precursor gas to the substrate within the chambereffective to form a first monolayer on the substrate; flowing a secondprecursor gas different in composition from the first precursor gas tothe first monolayer within the chamber under surface microwave plasmaconditions within the chamber effective to react with the firstmonolayer and form a second monolayer on the substrate which isdifferent in composition from the first monolayer, the second monolayercomprising components of the first monolayer and the second precursor;and successively repeating said first and second precursor flowingseffective to form a mass of material on the substrate of the secondmonolayer composition.
 2. The method of claim 1 wherein the firstprecursor gas comprises TiCl₄ and the first monolayer comprisesTiCl_(x).
 3. The method of claim 1 wherein the first precursor gascomprises TiCl₄, the first monolayer comprises TiCl_(x), the secondprecursor gas comprises B₂H₆, and the second monolayer comprises TiB₂.4. The method of claim 1 wherein the first precursor gas comprisesTiCl₄, the first monolayer comprises TiCl_(x), the second precursor gascomprises B₂H₆, the second monolayer comprises, and the mass is formedto consist essentially of TiB₂.
 5. The method of claim 1 wherein thefirst precursor gas comprises TiCl₄, the first monolayer comprisesTiCl_(x), the second precursor gas comprises B₂H₆, the second monolayercomprises TiB₂, and the mass is formed to consist of TiB₂.
 6. The methodof claim 1 wherein the first precursor gas flowing is void of plasmawithin the chamber.
 7. The method of claim 1 wherein the first precursorgas flowing is void of surface microwave plasma within the chamber. 8.The method of claim 1 wherein the first precursor gas flowing comprisesplasma within the chamber.
 9. The method of claim 1 wherein the firstprecursor gas flowing comprises surface microwave plasma within thechamber.
 10. The method of claim 1 wherein the first monolayer is of acomposition which is substantially unreactive with the second precursorunder otherwise identical processing conditions but for presence ofsurface microwave plasma within the chamber.
 11. The method of claim 1wherein the first precursor gas comprises TaCl₅ and the first monolayercomprises TaCl_(x).
 12. The method of claim 1 wherein the firstprecursor gas comprises TaCl₅, the first monolayer comprises TaCl_(x),the second precursor gas comprises NH₃, and the second monolayercomprises TaN.
 13. The method of claim 1 wherein the first precursor gascomprises TaCl₅, the first monolayer comprises TaCl_(x), the secondprecursor gas comprises NH₃, the second monolayer comprises TaN, and themass is formed to consist essentially of TaN.
 14. The method of claim 1wherein the first precursor gas comprises TaCl₅, the first monolayercomprises TaCl_(x), the second precursor gas comprises NH₃, the secondmonolayer comprises TaN, and the mass is formed to consist of TaN. 15.The method of claim 1 wherein the component of the first monolayercomprises a metal in elemental form.
 16. The method of claim 1 whereinthe second monolayer comprises a conductive metal compound, and the massof material is conductive.
 17. The method of claim 1 wherein the secondmonolayer comprises a dielectric, and the mass of material isinsulative.
 18. An atomic layer deposition method comprising:positioning a semiconductor substrate within an atomic layer depositionchamber; flowing a first precursor gas to the substrate within thechamber effective to form a first monolayer on the substrate; flowing asecond precursor gas different in composition from the first precursorgas to the first monolayer within the chamber under surface microwaveplasma conditions within the chamber effective to react with the firstmonolayer and form a second monolayer on the substrate which isdifferent in composition from the first monolayer, the second monolayercomprising components of the first monolayer and the second precursor;and after the second precursor gas flowing, flowing a third precursorgas different in composition from the first and second precursor gasesto the second monolayer within the chamber effective to react with thesecond monolayer and form a third monolayer on the substrate which isdifferent in composition from the first and second monolayers.
 19. Themethod of claim 18 successively repeating said first, second and thirdprecursor flowings effective to form a mass of material on the substratecomprising the third monolayer composition.
 20. The method of claim 18successively repeating said first, second and third precursor flowingseffective to form a mass of material on the substrate consistingessentially of the third monolayer composition.
 21. The method of claim18 successively repeating said first, second and third precursorflowings effective to form a mass of material on the substrateconsisting of the third monolayer composition.
 22. The method of claim18 wherein the first precursor gas comprises TiCl₄ and the firstmonolayer comprises TiCl_(x).
 23. The method of claim 18 wherein thefirst precursor gas comprises TiCl₄, the first monolayer comprisesTiCl_(x), and the second precursor gas comprises H₂.
 24. The method ofclaim 18 wherein the first precursor gas comprises TiCl₄, the firstmonolayer comprises TiCl_(x), the second precursor gas comprises H₂, thethird precursor gas comprises NH₃, and the third monolayer comprisesTiN.
 25. The method of claim 18 wherein at least one of the first andthird precursor gas flowings are void of plasma within the chamber. 26.The method of claim 18 wherein at least one of the first and thirdprecursor gas flowings are void of surface microwave plasma within thechamber.
 27. The method of claim 18 wherein both the first and thirdprecursor gas flowings are void of plasma within the chamber.
 28. Themethod of claim 18 wherein at least one of the first and third precursorgas flowings are void of surface microwave plasma within the chamber.29. The method of claim 18 wherein at least one of the first and thirdprecursor gas comprises plasma within the chamber.
 30. The method ofclaim 18 wherein at least one of the first and third precursor gasflowings comprise surface microwave plasma within the chamber.
 31. Themethod of claim 18 wherein both the first and third precursor gasflowings comprise plasma within the chamber.
 32. The method of claim 18wherein both of the first and third precursor gas flowings comprisesurface microwave plasma within the chamber.
 33. The method of claim 18wherein the first monolayer is of a composition which is substantiallyunreactive with the second precursor under otherwise identicalprocessing conditions but for presence of surface microwave plasmawithin the chamber.
 34. The method of claim 18 wherein the firstprecursor gas comprises trimethylaluminum and the first monolayercomprises AlCH_(X).
 35. The method of claim 18 wherein the firstprecursor gas comprises trimethylaluminum, the first monolayer comprisesAICHX, and the second precursor gas comprises H₂.
 36. The method ofclaim 18 wherein the first precursor gas comprises trimethylaluminum,the first monolayer comprises AlCH_(X), the second precursor gascomprises H₂, the third precursor gas comprise NH₃, and the thirdmonolayer comprises Al₂O₃.
 37. The method of claim 18 wherein the firstprecursor gas comprises TaCl₅ and the first monolayer comprisesTaCl_(x).
 38. The method of claim 18 wherein the first precursor gascomprises TaCl₅, the first monolayer comprises TaCl_(x), and the secondprecursor gas comprises H₂.
 39. The method of claim 18 wherein the firstprecursor gas comprises TaCl₅, the first monolayer comprises TaCl_(x),the second precursor gas comprises H₂, the third precursor gas comprisesNH₃, and the third monolayer comprises TaN.
 40. An atomic layerdeposition method comprising: positioning a semiconductor substratewithin an atomic layer deposition chamber; flowing a first precursor gasto the substrate within the chamber effective to form a first monolayeron the substrate; flowing a second precursor gas different incomposition from the first precursor gas to the first monolayer withinthe chamber under surface microwave plasma conditions within the chambereffective to react with the first monolayer and form a second monolayeron the substrate which is different in composition from the firstmonolayer, the second monolayer comprising components of the firstmonolayer and the second precursor; and after the second precursor gasflowing, flowing the first precursor gas to the substrate within thechamber effective to react with the second monolayer and both a) removea component of the second monolayer to form a third compositionmonolayer on the substrate which is different in composition from thefirst and second monolayers; and b) form a fourth monolayer of the firstmonolayer composition on the third composition monolayer.
 41. The methodof claim 40 wherein the third composition monolayer comprises a metal inelemental form.
 42. The method of claim 40 wherein the removed componentcomprises hydrogen.
 43. The method of claim 40 wherein the removedcomponent comprises elemental hydrogen.
 44. The method of claim 40wherein the first precursor gas flowing is void of plasma within thechamber.
 45. The method of claim 40 wherein the first precursor gasflowing is void of surface microwave plasma within the chamber.
 46. Themethod of claim 40 wherein the first precursor gas flowing comprisesplasma within the chamber.
 47. The method of claim 40 wherein the firstprecursor gas flowing comprises surface microwave plasma within thechamber.
 48. The method of claim 40 wherein the first monolayer is of acomposition which is substantially unreactive with the second precursorunder otherwise identical processing conditions but for presence ofsurface microwave plasma within the chamber.
 49. The method of claim 40wherein the first precursor gas comprises TiCl₄, the first monolayercomprises TiCl_(x), the second precursor comprises H₂, and the thirdcomposition monolayer comprises elemental titanium.
 50. The method ofclaim 40 wherein the first precursor gas comprises TaCl₅, the firstmonolayer comprises TaCl_(x), the second precursor comprises H₂, and thethird composition monolayer comprises elemental tantalum.
 51. An atomiclayer deposition method, comprising; positioning a semiconductorsubstrate within an atomic layer deposition chamber; flowing a firstprecursor gas to the substrate within the chamber effective to form afirst monolayer on the substrate; after forming the first monolayer,flowing an inert purge gas to the chamber; after flowing the inert purgegas, flowing a second precursor gas to the substrate under plasmaconditions within the chamber effective to form a second monolayer onthe substrate which is different in composition from the firstmonolayer, the second precursor gas being different in composition fromthe first precursor gas, said plasma conditions comprising applicationof energy to the chamber at a power level capable of sustaining plasmaconditions within the chamber with the second precursor gas; andcommencing application of said energy to the chamber at an increasingpower level up to said plasma capable power level prior to flowing thesecond precursor gas to the chamber.
 52. The method of claim 51 whereinthe inert purge gas and second precursor gas flowings do not overlap.53. The method of claim 51 wherein the inert purge gas- and secondprecursor gas flowings overlap.
 54. The method of claim 51 wherein theinert purge gas and second precursor gas flowings overlap, andcomprising ceasing the inert purge gas flowing after a ceasing of thesecond precursor gas flowing.
 55. The method of claim 51 comprisingafter forming the second monolayer, commencing another inert purge gasflowing prior to commencing a reducing of the plasma capable power. 56.The method of claim 55 wherein the second precursor and another inertpurge gas flowings do not overlap.
 57. The method of claim 51 comprisingceasing flow of the second precursor gas to the chamber prior tocommencing a reducing of the plasma capable power.
 58. The method ofclaim 51 comprising: after forming the second monolayer, commencinganother inert purge gas flowing prior to commencing a reducing of theplasma capable power; and ceasing flow of the second precursor gas tothe chamber prior to commencing said reducing of the plasma capablepower.
 59. The method of claim 51 wherein the plasma conditions comprisesurface microwave plasma.
 60. The method of claim 51 wherein saidincreasing is continuous.
 61. The method of claim 51 wherein the firstprecursor gas comprises TiCl₄, the first monolayer comprises TiCl_(x),and the second precursor gas comprises H₂.
 62. The method of claim 51wherein the first monolayer is formed in the absence of plasma withinthe chamber.
 63. The method of claim 51 wherein the second monolayerreacts with the first monolayer, the second monolayer comprisingcomponents of the first monolayer and the second precursor.
 64. Anatomic layer deposition method, comprising; positioning a semiconductorsubstrate within an atomic layer deposition chamber; flowing a firstprecursor gas to the substrate within the chamber effective to form afirst monolayer on the substrate; after forming the first monolayer,flowing an inert purge gas to the chamber; after flowing the inert purgegas, flowing a second precursor gas to the substrate under plasmaconditions within the chamber effective to form a second monolayer onthe substrate which is different in composition from the firstmonolayer, the second precursor gas being different in composition fromthe first precursor gas, the second precursor gas flowing under plasmaconditions within the chamber commencing before a ceasing of the inertpurge gas flowing; and ceasing the inert purge gas flowing aftercommencing and while said flowing of the second precursor gas underplasma conditions within the chamber.
 65. The method of claim 64comprising after forming the second monolayer, commencing another inertpurge gas flowing prior to a ceasing of the second precursor gas flowingto the chamber.
 66. The method of claim 64 wherein the plasma conditionscomprise application of energy to the chamber at a power level capableof sustaining plasma conditions within the chamber with the secondprecursor gas; and commencing application of said energy to the chamberat an increasing power level up to said plasma capable power levelcommensurate with commencing flow of the second precursor gas to thechamber.
 67. The method of claim 64 wherein the plasma conditionscomprise application of energy to the chamber at a power level capableof sustaining plasma conditions within the chamber with the secondprecursor gas; and commencing application of said energy to the chamberat an increasing power level up to said plasma capable power level priorto commencing flow of the second precursor gas to the chamber.
 68. Themethod of claim 64 wherein the plasma conditions comprise application ofenergy to the chamber at a power level capable of sustaining plasmaconditions within the chamber with the second precursor gas; andcommencing application of said energy to the chamber at an increasingpower level up to said plasma capable power level after commencing flowof the second precursor gas to the chamber.
 69. The method of claim 64wherein the plasma conditions comprise surface microwave plasma.
 70. Themethod of claim 64 wherein the first precursor gas comprises TiCl₄, thefirst monolayer comprises TiCl_(x), and the second precursor gascomprises H₂.
 71. The method of claim 64 wherein the second monolayerreacts with the first monolayer, the second monolayer comprisingcomponents of the first monolayer and the second precursor.
 72. Anatomic layer deposition method, comprising; positioning a semiconductorsubstrate within an atomic layer deposition chamber; flowing a firstprecursor gas to the substrate within the chamber effective to form afirst monolayer on the substrate; after forming the first monolayer,flowing a second precursor gas to the substrate under plasma conditionswithin the chamber effective to form a second monolayer on the substratewhich is different in composition from the first monolayer, the secondprecursor gas being different in composition from the first precursorgas, plasma generation of the second precursor gas within the chamberoccurring from a second applied power of energy to the chamber, andfurther comprising applying a steady state first applied power of saidenergy to the chamber prior to applying said second applied power ofsaid energy, the steady state first applied power being less than thesecond applied power and increasing the first applied power to saidsecond applied power.
 73. The method of claim 72 wherein said increasingis continuous.
 74. The method of claim 72 wherein the steady state firstpower is insufficient to generate plasma from flowing the secondprecursor gas.
 75. The method of claim 72 wherein the steady state firstpower is insufficient to generate plasma from flowing the firstprecursor gas.
 76. The method of claim 72 comprising applying the steadystate first power during the first precursor flowing.
 77. The method ofclaim 76 wherein the steady state first power is insufficient togenerate plasma from the flowing first precursor gas.
 78. The method ofclaim 72 comprising flowing an inert purge gas to the chamberintermediate the first and second precursor gas flowings.
 79. The methodof claim 78 comprising applying the steady state first power during theinert purge gas flowing.
 80. The method of claim 78 comprising flowingan inert purge gas to the chamber after the second precursor gasflowing, applying the steady state first power during the inert purgegas flowing intermediate the first and second precursor gas flowings andapplying the steady state first power during the inert purge gas flowingafter the second precursor flowing.
 81. The method of claim 72 whereinthe plasma conditions comprise surface microwave plasma.
 82. The methodof claim 72 comprising commencing the increasing prior to commencing thesecond precursor gas flowing.
 83. The method of claim 72 comprisingcommencing the increasing after commencing the second precursor gasflowing.
 84. The method of claim 72 comprising commencing the increasingcommensurate with commencing the second precursor gas flowing.
 85. Themethod of claim 72 comprising reducing power to the steady state firstpower after a ceasing flow of the second precursor gas.
 86. The methodof claim 72 comprising reducing power to the steady state first powerprior to a ceasing flow of the second precursor gas.
 87. The method ofclaim 72 wherein the first precursor gas comprises TiCl₄, the firstmonolayer comprises TiCl_(x), and the second precursor gas comprises H₂.88. An atomic layer deposition method, comprising; positioning asemiconductor substrate within an atomic layer deposition chamber;applying a base power level of energy to the chamber with the substratepositioned therein; while applying the base power level of energy,flowing a first precursor gas to the substrate within the chambereffective to form a first monolayer on the substrate under non-plasmaconditions within the chamber; after forming the first monolayer,raising the base power level of said energy to a power level capable ofgenerating plasma within the chamber; flowing a second precursor gas tothe substrate within the chamber while said plasma capable power levelof said energy is applied to the chamber effective to form a plasma withsaid second precursor gas against the first monolayer to form a secondmonolayer on the substrate which is different in composition from thefirst monolayer; and after forming the second monolayer, reducing theplasma capable power level of said energy to the base power level andthereafter depositing another monolayer onto the second monolayer. 89.The method of claim 88 wherein said raising is continuous.
 90. Themethod of claim 88 comprising flowing an inert purge gas to the chamberintermediate the first and second precursor gas flowings.
 91. The methodof claim 90 comprising applying the base power level of energy duringthe inert purge gas flowing.
 92. The method of claim 90 comprisingflowing an inert purge gas to the chamber after the second precursor gasflowing, applying the base power level of energy during the inert purgegas flowing intermediate the first and second precursor gas flowings andapplying the base power level of energy during the inert purge gasflowing after the second precursor flowing.
 93. The method of claim 88wherein the plasma comprises surface microwave plasma.
 94. The method ofclaim 88 comprising commencing the raising prior to commencing thesecond precursor gas flowing.
 95. The method of claim 88 comprisingcommencing the raising after commencing the second precursor gasflowing.
 96. The method of claim 88 comprising commencing the raisingcommensurate with commencing the second precursor gas flowing.
 97. Themethod of claim 88 comprising commencing said reducing after a ceasingflow of the second precursor gas.
 98. The method of claim 88 comprisingcommencing said reducing prior to a ceasing flow of the second precursorgas.
 99. The method of claim 88 wherein the first precursor gascomprises TiCl₄, the first monolayer comprises TiCl_(x), and the secondprecursor gas comprises H₂.